$\dfrac{1}{2} + \dfrac{4}{10} = {?}$
Explanation: ${\dfrac{1}{2}}$ ${\dfrac{4}{10}}$ $+$ ${\dfrac{1 \times 5}{2 \times 5}}$ ${\dfrac{4 \times 1}{10 \times 1}}$ $+$ ${\dfrac{5}{10}}$ ${\dfrac{4}{10}}$ $+$ $ = \dfrac{{5} + {4}}{10} $ $ = \dfrac{9}{10}$